Nevoid Melanoma - The Unique Histological and Immunohistochemical Appearance

Abstract

Nevoid melanoma is a rare tumor with the origin in the melanin-producing cells called melanocytes. The main particularity of this tumor is the resemblance with a benign tumor, a compound of intradermal nevi, despite the malignant behavior and aggressivity. On the usual stain, we generally observe a tumoral proliferation with a solid architecture, with cells organized in nests. The cytological atypia is observed with high power fields; pagetoid migration is common. The cases described so far in the literature are limited and the incidence has not been established due to the variety of diagnostic definitions for this particular tumor.